JP2011192788A - Metalized film capacitor, metalized film capacitor device, and method of manufacturing them - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide: a metalized film capacitor which is enhanced in moisture resistance and heat dissipation, and suppresses product weight to be low; a metalized film capacitor device; and a method of manufacturing them. <P>SOLUTION: The metalized film capacitor includes: a capacitive element (6) which has an electrode part at one electrode layer configured by spraying metal on an element end face and an electrode part at the other electrode layer configured by spraying metal on an element end face while at least two dielectric films (56 and 58) each having an electrode layer are wound; an exterior member (exterior container 8) having an opening (28) on each element end face side of the capacitive element; sealing members (cover parts 10 and 12) which seal the exterior member with gaps left between the sealing members and the element end faces of the capacitive element; terminal parts (14 and 16) penetrating the sealing members and fixed to them; lead parts (30 and 32) connecting the terminal parts and electrode parts; and a sealing resin (18) charged in the gaps (D<SB>5</SB>) between the sealing members and exterior member to cover the electrode parts and be brought into close contact with the sealing members to seal the exterior member and sealing members. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to a capacitor using a dry-type metallized film capacitor element, a capacitor device, and a manufacturing method thereof. For example, the present invention relates to a metallized film capacitor, a metallized film capacitor device, and a manufacturing method thereof used in the field of power electronics.

  In the field of power electronics such as a high output power source, a metallized film capacitor is used for a smoothing element or the like. Such metallized film capacitors are required to have a high withstand voltage and a large capacity. When the withstand voltage and capacity required for metallized film capacitors exceed the withstand voltage and capacity of a single element, multiple elements are electrically connected to increase the breakdown voltage by series connection and large capacity by parallel connection. High voltage resistance and large capacity are achieved by using a parallel or serial-parallel connection.

  For metallized film capacitors, in order to achieve a high withstand voltage and large capacity, a wet type in which an insulating oil is impregnated using a metallized film obtained by vapor-depositing aluminum or the like on a polypropylene film has been used. The oil impregnated with insulating oil is large and heavy, and if flammable insulating oil is used, there is a drawback that it easily burns.

  With regard to such a metallized film capacitor, a dry metallized film capacitor assembly is known in which a plurality of elements are connected to form a capacitor element assembly, which is covered with urethane resin, epoxy resin, or the like ( Patent Document 1).

  In resin-filled dry metallized film capacitor assemblies, cracks are likely to occur in the resin filled in the case due to shrinkage during heat curing, and the connected capacitor element assembly is subject to thermal stress caused by heating during resin curing. There is a risk of physical stress due to resin cracks.

  When a crack is generated in the filling resin, when a moisture resistance load test is performed, moisture enters from the crack. This moisture causes oxidative degradation of the metal vapor deposition electrode of each capacitor element that has not been subjected to a treatment such as coating. Oxidative deterioration of the electrode will cause the electrode function to be lost and the capacitance to be lost.

  When the capacitor element is subjected to thermal stress or physical stress during resin curing, the polypropylene film constituting the capacitor element is softened or deformed, the wound body itself is deformed, the dielectric film of one metallized film and the other metal There is an inconvenience that a void portion that impairs adhesion is generated between the vapor deposition film and the aluminum vapor deposition film, and as a result, the initial capacitance is lowered.

  When a high current is passed through a metallized film capacitor assembly in which a plurality of capacitor elements are assembled, a bus bar such as a copper plate is used for the connection. When connecting the electrode parts of multiple capacitor elements with a bus bar, if the position of each element is shifted during resin curing or stress is applied to the connection part between the element electrode part and the bus bar, the connection state deteriorates and the resistance of the connection part This causes heat generation at the increase or connection portion, resulting in a decrease in the breakdown voltage of the capacitor element and a short circuit failure.

  When the entire capacitor element assembly is covered with the filling resin, the filling resin deteriorates the heat dissipation of the capacitor element assembly, and there are disadvantages such as an increase in the temperature and weight of the capacitor element assembly during use.

In order to solve such a problem, a resin dip is applied to the capacitor elements, and a plurality of capacitor elements are connected by lead wires drawn from the capacitor elements, and then stored in a case. In that case, the resin is filled to about 10 to 90% of the height of the capacitor element, and the capacitor element itself has moisture resistance to improve the moisture resistance characteristics of the capacitor assembly and reduce the resin filling amount. In order to improve heat dissipation and suppress the temperature rise, it is known (Patent Document 2).

JP 2000-299245 A JP 2004-319799 A

  By the way, in the metallized film capacitor | condenser assembly which formed the resin layer by the dip (patent document 2), it is difficult to form in a uniform resin layer, and a non-uniform resin layer varies in moisture resistance. Also, the element end face corresponding to the cylindrical corner, that is, the resin layer of the element electrode part (metallicon electrode) subjected to metal spraying (metallicon) becomes thin.

  In a metallicon electrode having a porous structure, water vapor easily enters the capacitor element. On the other hand, the moisture permeability of the polypropylene film of the wound element is low, and the polypropylene film exposed on the side surface of the element does not become a water vapor intrusion path, and its influence is low. Therefore, the resin layer covering the metallicon electrode is required to have sufficient moisture resistance, but in the resin layer by dipping, the resin layer is thin at the metallicon electrode part and the uniformity thereof varies, so that the moisture resistance effect is sufficient. I can't say that.

  The filling resin applied to the capacitor element assembly covers only about 10 to 90% of the element height, so that the moisture resistance necessary for the metallicon electrode portion of each capacitor element cannot be satisfied.

  The filling resin that covers the capacitor element assembly covers the entire capacitor element assembly even if the amount of the filled resin is reduced to a certain extent, so that the hardening applies a large thermal stress or physical stress to the capacitor element, and the initial It causes deterioration of the characteristics.

  In addition, the crack of the filling resin is likely to occur at the interface between the filling resin surface where the capacitor element is exposed and the capacitor element, that is, many of the cracks occur at a place where the filling resin requires a moisture resistance function. For this reason, a crack reduces the intrusion prevention effect of moisture by the filling resin.

  Furthermore, the amount of filled resin is greatly related to the exposed area of the capacitor element, that is, if the amount of filled resin is small, the exposed area of each capacitor element is widened, and heat dissipation is improved, but moisture resistance is lowered. Further, if the amount of the filled resin is large, the exposed area of each capacitor element is narrowed and the moisture resistance is improved, but the heat dissipation is deteriorated.

  Thus, the conventional dry-type metallized film capacitor assembly has insufficient moisture resistance and heat dissipation, and further has a problem that the product weight cannot be suppressed.

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a metallized film capacitor, a metallized film capacitor device, and a manufacturing method thereof that improve moisture resistance and heat dissipation and suppress the product weight.

  The metallized film capacitor of the present invention that has solved the above problems is a winding element in which at least two dielectric films each having an electrode layer are wound, and one end of the electrode layer is formed by spraying metal onto the end face of the element. A capacitor element having an electrode portion connected to the other end of the electrode layer formed by spraying metal on the element end face, and an opening on each element end face side of the capacitor element, and the capacitor A space is provided between the exterior member that houses the element and the element end surface of the capacitor element, and is fixed to the exterior member, and a sealing member that seals each of the openings, and is fixed to penetrate the sealing member. A terminal portion, a lead portion fixed to and electrically connected to the terminal portion, and connecting the terminal portion and the electrode portion, and the space between the sealing member and the exterior member is filled. It is, and a sealing resin said electrode portions over and in close contact with the sealing member so sealed and the sealing member and the outer member.

  Further, in the metallized film capacitor, the sealing member includes a closed portion that covers an opening end surface of the exterior member, and a standing wall portion that is formed at a peripheral portion of the closed portion and covers a peripheral surface of the exterior member. The sealing resin may be filled between the standing wall portion and the exterior member.

In the metallized film capacitor, the thickness d of at least one of the sealing resin or the exterior member may be a value equal to or greater than a value of the following formula.
d = 1.63 · k · (h / 2000) · (P / P0) or more.
d: Thickness (mm)
k: moisture permeability (g · mm / mm ² · 24h)
h: Moisture resistance reliability guarantee time (hours)
P: Water vapor pressure (Pa) under moisture resistance guarantee test conditions
P0: Water vapor pressure at 85 ° C. and 85% RH (Pa)

  The metallized film capacitor device of the present invention that has solved the above problems is a capacitor assembly in which a plurality of the metallized film capacitors are juxtaposed, and between one or the other terminal portion of the metallized film capacitor of the capacitor assembly. And a plurality of the metallized film capacitors connected in series, in parallel or in series and parallel by the bus bar.

  The method for producing a metallized film capacitor of the present invention that has solved the above problems is a winding element in which at least two dielectric films each having an electrode layer are wound, and the electrode is formed by spraying metal onto the element end face. Forming a capacitor element comprising an electrode part connected to one of the layers, an electrode part connected to the other of the electrode layers formed by spraying metal on the element end face, and on each element end face side of the capacitor element A step of forming an exterior member having an opening and accommodating the capacitor element; and a lead portion that connects the terminal portion and the electrode portion together with the terminal portion, and provides an interval between the element end face of the capacitor element A step of forming a sealing member that is fixed to the exterior member and seals each of the openings, and the exterior member and the sealing portion that cover the electrode portion and are in close contact with the sealing member And a step of filling in the gap in between the outer member and the sealing resin and the sealing member for sealed and.

The method for producing a metallized film capacitor device of the present invention that has solved the above problems includes a step of forming a capacitor assembly by juxtaposing a plurality of metallized film capacitors obtained by the method for producing a metallized film capacitor, Connecting one or the other terminal of the metallized film capacitor of the capacitor assembly with a bus bar, and connecting the plurality of metallized film capacitors in series, parallel, or series-parallel.

  According to the metallized film capacitor and the manufacturing method thereof of the present invention, the following effects can be obtained.

  (1) Resin sealing can be performed with the exterior member, the sealing member, and the sealing resin, and the moisture resistance of the capacitor element can be improved.

  (2) Since the opening of the exterior member is sealed with the sealing resin, the adhesiveness with the capacitor element is good, and water vapor intrusion from the interface between the capacitor element and the sealing resin can be suppressed.

  (3) With the exterior member and the sealing member, the layer thickness of the sealing resin can be adjusted to be constant, and uniform sealing characteristics, sealing strength, and moisture resistance can be obtained.

  (4) The layer thickness of the sealing resin can be adjusted according to the moisture resistance guarantee conditions, and the product weight and size can be suppressed and uniformized.

  (5) The terminal part is fixed to the sealing member, and the terminal part and the electrode part of the capacitor element are connected by a fixed lead part, so that the connection length can be minimized, the resistance is reduced, and the metallized film Capacitor weight and size can be reduced.

  (6) Since the exterior member, the sealing member, the capacitor element, and the terminal portion are fixed with a single sealing resin, it is possible to stabilize the connection state as well as stabilizing the fixing strength thereof.

  (7) Since the sealing resin for fixing the exterior member and the sealing member is in close contact with the capacitor element, the water vapor intrusion path can be made long and narrow, and the moisture resistance of the capacitor element can be improved.

  (8) If the thickness of the exterior member or the sealing resin is set so as to satisfy the above-described formula, it is possible to reliably and sufficiently improve the moisture resistance and to guarantee a certain moisture resistance.

  (9) The amount of resin used for the sealing resin can be controlled at a constant level, and the capacitor element can be protected from thermal and physical stress during curing shrinkage of the sealing resin, and the initial characteristics are stabilized. A metallized film capacitor provided with a capacitor element can be provided.

  According to the metallized film capacitor device and the manufacturing method thereof of the present invention, the following effects can be obtained.

  (1) According to the metallized film capacitor device of the present invention, since the metallized film capacitor described above is used as an assembly, the effects described in the above (1) to (9) can be enjoyed, and the moisture resistance Thus, it is possible to provide a capacitor device that is smaller and more robust.

  (2) A terminal portion is formed on each end face of the metallized film capacitor, and the first and second bus bars are arranged and connected to different end faces of the different metallized film capacitors. Can increase safety.

Other objects, features, and advantages of the present invention will become clearer with reference to the accompanying drawings and each embodiment.

It is sectional drawing which shows an example of the metallized film capacitor which concerns on 1st Embodiment. It is a disassembled perspective view which decomposes | disassembles and shows a metallized film capacitor. It is a perspective view which decomposes | disassembles and shows an example of a capacitor | condenser element. It is sectional drawing which shows an example of the resin sealing process of a metallized film capacitor. It is a figure which shows an example of the creeping distance of sealing resin. It is a perspective view which notches and shows a part of metallized film capacitor | condenser apparatus which concerns on 2nd Embodiment. It is a figure which shows an example of the connection of a metallized film capacitor and a bus bar, and an insulation cover. It is a figure which shows the equivalent circuit of a metallized film capacitor | condenser apparatus. It is sectional drawing which shows an example of the metallized film capacitor which concerns on 3rd Embodiment.

[First Embodiment]

  The first embodiment is an example of a structure of a metallized film capacitor as a single metallized film capacitor, a component of a metallized film capacitor device, and a method for manufacturing the same.

  The first embodiment will be described with reference to FIG. FIG. 1 shows an example of a metallized film capacitor.

  This metallized film capacitor 2 is an example of the metallized film capacitor of the present invention, and is a component of the metallized film capacitor device 4 of the present invention, for example, the metallized film capacitor device 4 (FIG. 6). However, the present invention is not limited to the components of the metallized film capacitor device 4.

  Therefore, this metallized film capacitor 2 includes a capacitor element 6, an outer container 8, lid portions 10 and 12, terminal portions 14 and 16, and a sealing resin 18.

  The capacitor element 6 is a metallized film capacitor element and is a winding element. A first electrode portion 20 is formed on one of the element end faces of the capacitor element 6, and a second electrode portion 22 is formed on the other end. These electrode portions 20 and 22 are formed of a metal having good conductivity by metal forming means such as metallicon on the first or second electrode layers 24 and 26 (FIG. 3) exposed on the element end face of the capacitor element 6. Yes. That is, the electrode portion 20 is a connecting means with one electrode layer 24 (FIG. 3) of the capacitor element 6, and the electrode portion 22 is a connecting means with the other electrode layer 26 (FIG. 3). The capacitor element 6 is housed inside the outer container 8.

The exterior container 8 is an example of an exterior member of the capacitor element 6, and is a cylindrical body having a volume and an inner diameter that can accommodate the capacitor element 6, and includes openings 28 at both ends. The outer container 8 of this embodiment is, for example, a synthetic resin molded body as an insulating material, but may be a metallic cylinder. When the element length of the capacitor element 6 is L ₁ , the element diameter is D ₁ , the outer container 8 is L ₂ and the inner diameter is D ₂ , L ₁ <L ₂ and D ₁ <D ₂ may be satisfied.

Here, L ₂ −L ₁ = ΔDa is a width that forms a space on each element end side of the capacitor element 6 in the outer casing 8. This space is a volume portion for filling a sufficient amount of sealing resin 18 for sealing. In this embodiment, the terminal portions 14 and 16 and their connecting portions are accommodated in the width ΔDa. Therefore, in this embodiment, a minimum width ΔDa that can accommodate these is set. That is, a width of ΔDa / 2 is set on each element end side.

The lid portions 10 and 12 are an example of a sealing member that closes the opening portion 28 of the exterior container 8. In this embodiment, the lid portions 10 and 12 are formed of a synthetic resin in the same manner as the exterior container 8. When the outer diameter of the outer container 8 is D ₃ and the inner diameters of the lid portions 10 and 12 are D ₄ , D ₃ <D ₄ is set. When D ₄ −D ₃ = Db, the set width Db allows the lid portions 10 and 12 to be attached to the opening 28 of the outer container 8 and the sealing resin 18 within an interval set by the width Db. It is a means to penetrate. Further, a gap D ₅ is set between the lid portions 10 and 12 and the opening end of the outer container 8.

  The terminal portions 14 and 16 are terminals corresponding to the electrode layers 24 and 26 of the capacitor element 6 and are external connection means. The terminal portion 14 is fixed through the lid portion 10, and the terminal portion 16 is a lid portion. 12 is fixed through. In this embodiment, the electrode part 20 is connected to the terminal part 14 by a lead part 30. In addition, the electrode portion 22 is connected to the terminal portion 16 by a lead portion 32. The connection between the electrode part 20 and the lead part 30 and the connection between the electrode part 22 and the lead part 32 may be connected by soldering, for example, and 31 is a connection part.

The sealing resin 18 is a resin that fills the space on the opening 28 side of the outer container 8 that is closed with the lid portions 10 and 12, and is, for example, an epoxy resin as a thermosetting resin having a high sealing property. Or urethane resin. The sealing resin 18 is provided between the lid portions 10 and 12 and the element end surface of the capacitor element 6, between the capacitor element 6 and the outer container 8, and between the opening end of the outer container 8 and the lid portions 10 and 12. _5. wraps between the edge of the opening 28 of the outer container 8 and the lids 10 and 12 to form a highly airtight sealing structure, and fixes these members together Functions as a fixing means. In other words, the capacitor element 6, the outer container 8, and the lid portions 10 and 12 are integrated by the sealing resin 18.

  The lid portions 10 and 12 and the terminal portions 14 and 16 of the metallized film capacitor 2 are referred to FIG. FIG. 2 shows an exploded view of the metallized film capacitor.

Each cover part 10 and 12 is provided with the obstruction | occlusion part 34 and the standing wall part 36, and if the obstruction | occlusion part 34 is made into a bottom part, it will be formed in the bottomed cylindrical shape. The closing part 34 is, for example, a disk having a larger diameter than each opening 28 of the outer container 8 that houses the capacitor element 6. A standing wall portion 36 having a constant width is formed at the peripheral portion of the closing portion 34. The width D ₆ of the blocking portion 34 is larger than the added value (D ₅ + ΔDa / 2) of the interval D ₅ and the width ΔDa / 2, that is, D ₆ > (D ₅ + ΔDa / 2). You only have to set it.

  A through hole 38 is formed in the central portion of the closing portion 34, and the terminal bolts 40 of the terminal portion 14 or the terminal portion 16 are passed through and fixed to the through hole 38. The terminal bolt 40 includes a head portion 42 having a diameter larger than that of the through hole 38 and a screw portion 44. The head part 42 is installed inside the lid parts 10 and 12, and the packing 46 and the lead part 30 or the lead part 32 are installed inside the lid parts 10 and 12 as disc-shaped sealing members.

  The screw part 44 of the terminal bolt 40 is passed through the through hole 48 of the packing 46 and the connection hole 50 of the lead part 30 or the lead part 32. A packing 46 and a lead portion 30 or 32 are sandwiched between the inner surface portions of the lid portions 10 and 12 and the head portion 42 of the terminal bolt 40, and a washer 52 and a screw portion 44 penetrating the closing portion 34 are provided. By attaching the nut 54, the terminal portion 14 is attached to the lid portion 10, and the terminal portion 16 is attached to the lid portion 12. In this case, the through hole 38 is closed by the packing 46, and the lead portion 30 or 32 is electrically connected to the terminal bolt 40.

  The lead part 30 connected to the terminal part 14 is connected to the electrode part 20 of the capacitor element 6 by connection means such as soldering, and the lead part 32 connected to the terminal part 16 is connected to the electrode part 22 of the capacitor element 6. They are connected by the same connecting means.

  Next, the capacitor element 6 is referred to FIG. FIG. 3 shows a configuration example of the capacitor element.

  The capacitor element 6 includes at least two strip-shaped dielectric films 56 and 58 having a constant width. The first electrode layer 24 is formed on one surface side of the dielectric film 56, and one surface of the dielectric film 58. On the side, a second electrode layer 26 is formed. The dielectric films 56 and 58 have the electrode layers 24 and 26 formed with the width a and the electrodeless portions 60 formed with the width b. The electrodeless portions 60 are formed on the dielectric films 56 and 58. Are provided on different edge sides. Therefore, the electrode layer 24 is exposed at one element end face of the capacitor element 6 and the edge of the electrode layer 26 is exposed at the other element end face. In other words, one end face of each element is the electrode layer 24 and the other end face. Is formed of the electrode layer 26.

  Next, FIG. 4 is referred to for an example of a method for manufacturing a metallized film capacitor. FIG. 4 is a diagram illustrating a resin sealing procedure.

  The manufacturing process of the metallized film capacitor 2 includes an element formation process and an assembly process, and the assembly process includes a resin sealing process (FIG. 4). In the element formation step, the capacitor element 6 described above is formed. In the assembly process, the metallized film capacitor 2 is assembled through the manufacture of the external container 8, the lid portions 10 and 12, and the terminal portions 14 and 16.

  In the pre-process of the resin sealing step, the capacitor element 6 is inserted into the outer container 8, and the lead portions 30 and 32 fixed to the electrode portions 20 and 22 of the capacitor element 6 and the terminal portions 14 and 16 of the lid portions 10 and 12. Is soldered.

  Therefore, for example, one lid 10 is filled with a predetermined amount of the liquefied sealing resin 18. The capacitor element 6 is inserted into the sealing resin 18 together with the outer casing 8 and positioned, and the sealing resin 18 is cured. The state shown in FIG. 4 is a state in which one lid 10 has already sealed the outer container 8 with the sealing resin 18 and shows a process leading to sealing on the lid 12 side.

  The metallized film capacitor 2 shown in FIG. 1 is assembled and commercialized through such a resin sealing process.

  Regarding the metallized film capacitor 2 and the manufacturing method thereof according to the first embodiment described above, reference will be made to the following features and the like.

  (1) The outer container 8 and the lid portions 10 and 12 are resin-sealed with the sealing resin 18, and the moisture resistance of the capacitor element 6 can be improved.

  (2) Since the opening 28 of the outer container 8 is sealed with the sealing resin 18, the adhesiveness between the sealing resin 18 and the capacitor element 6 is good, and the interface 28 between the capacitor element 6 and the sealing resin 18 Water vapor intrusion can be suppressed.

  (3) The outer container 8 and the lid portions 10 and 12 can adjust the layer thickness of the sealing resin 18 to be uniform, and uniform sealing characteristics, sealing strength, and moisture resistance can be obtained.

  (4) The layer thickness of the sealing resin 18 can be adjusted according to the moisture resistance guarantee conditions, and the product weight and size can be suppressed and uniformized.

  (5) Since the terminal portions 14 and 16 are fixed to the lid portions 10 and 12, and the terminal portions 14 and 16 and the electrode portions 20 and 22 of the capacitor element 6 are connected by lead portions 30 and 32 having a certain length, The connection length can be minimized, and the weight and size of the metallized film capacitor 2 can be suppressed together with the low resistance.

  (6) Since the exterior container 8, the lid parts 10 and 12, the capacitor element 6 and the terminal parts 14 and 16 are fixed with a single sealing resin 18, the fixing strength is stabilized and the connection state is stabilized. Can be planned.

  (7) Since the sealing resin 18 for fixing the outer container 8 and the lid portions 10 and 12 is closely attached to the capacitor element 6, the water vapor intrusion path can be made long and narrow, and the moisture resistance of the capacitor element 6 is improved. Can do.

  Here, FIG. 5 is referred with respect to this water vapor | steam penetration | invasion. FIG. 5 shows an example of the creeping distance of the sealing resin.

  The creepage distance ID of the sealing resin 18 that is in close contact with the outer container 8 is a distance from a point q1 outside the outer container 8 to a point q2 on the peripheral surface of the capacitor element 6. If this creepage distance ID is the water vapor intrusion path, the contact area between the outer container 8 and the sealing resin 18 is large, and the creepage distance ID is set to be considerably large. For this reason, since the water vapor intrusion path is long and narrow, the capacitor element 6 can be protected from water vapor intrusion.

  (8) If the thickness of the outer container 8 or the sealing resin 18 is set so as to satisfy the following formula (1), the moisture resistance performance can be surely and sufficiently improved and a certain moisture resistance guarantee can be performed.

The thickness d of at least one of the sealing resin 18 or the outer container 8 is
d = 1.63 · k · (h / 2000) · (P / P0) (1)
d: Thickness (mm)
k: moisture permeability (g · mm / mm ² · 24h)
h: Moisture resistance reliability guarantee time (hours)
P: Water vapor pressure (Pa) under moisture resistance guarantee test conditions
P0: Water vapor pressure at 85 ° C. and 85% RH (Pa)
And it is sufficient.

  In such a configuration, since the water vapor intrusion path is very narrow and long, the moisture resistance is very good.

  In addition, by defining the thickness of each sealing resin 18, it is possible to ensure a necessary and sufficient moisture resistance.

  (9) The amount of the sealing resin 18 can be controlled to be constant, the capacitor element 6 can be protected from thermal stress and physical stress during the curing shrinkage of the sealing resin 18, and the initial characteristics are stabilized. A metallized film capacitor 2 including the capacitor element 6 can be provided.

  (10) In the structure in which the terminal portions 14 and 16 are pulled out from both ends of the outer container 8, the outermost peripheral part is covered with polypropylene as a dielectric, so that the outer container 8 with respect to the side surface part of the element having relatively good moisture resistance. And the resin thickness of the electrode parts 20 and 22 that are the metallicon electrode parts most penetrating the water vapor, respectively, and the exposed parts of the screw parts 44 that are the metallicon electrode parts 20 and 22 and the externally exposed parts respectively. Not only can the resistance be suppressed to the shortest, but also the thickness of the resin layer of the sealing resin 18 covering the metallicon portion can be minimized, and the weight and size of the metallized film capacitor 2 can be minimized. Can do.

  (11) Since the amount of the resin of the sealing resin 18 can be managed sufficiently, there is no thermal stress or physical stress at the time of curing shrinkage of the filled resin as in the conventional case, and the capacitor element has stable initial characteristics. In addition to being less stressed, it is also possible to effectively reduce weight and size.

  (12) Regarding the above-mentioned formula (1),

  The general formula relating to the permeation of gas when the gas permeates the resin or the like is as follows.

A = k (p1-p2) .S / d (2)
However, A: Gas permeation amount
k: Gas permeability coefficient of resin
p1, p2: Gas partial pressure inside and outside the resin
S: Resin area (transmission cross section)
d: Resin thickness.

  When a moisture resistance test is performed on the metallized film capacitor 2, “there is no water vapor alone” and “the invading water reacts with the electrode metal and is consumed” inside the metallized film capacitor 2. Therefore, p2 is substantially “0”, and under a constant moisture resistance condition (for example, 85 ° C.-85% RH), the time taken for a certain amount of moisture penetration is proportional to the resin thickness and inversely proportional to the moisture permeability.

  Here, the thickness (up to the element) of the sealing resin whose moisture permeability was known was changed, and a moisture resistance load test was performed at 85 ° C. to 85% RH to confirm a change in capacitance (decrease).

  Capacitance reduction occurs due to vapor deposition metal degradation due to intrusion moisture, but product degradation time is A: time for moisture to permeate the sealing resin and reach the capacitor element, and B: electrode due to the moisture reached. It becomes the total time with the time to deteriorate.

Therefore, using a sealing resin of k1 (moisture permeability): 9.5 [g · mm / mm ² · 24 h], the sealing thickness is set to 5 [mm] and 10 [mm], and 85 [° C.]-85. [%] When the time when the capacitance change rate exceeds 5 [%] in the RH moisture resistance load test is obtained, when 5 [mm]: A + B = 950 [h], when 10 [mm]: A + B = 1450 [ h].

  Here, B is constant regardless of the resin thickness, and A is proportional to the resin thickness. Therefore, when A = a · d1, when 5 [mm]: 5a + B = 950 [h], 10 [mm] ]: 10a + B = 1450 [h].

  From the above formula, when a = 100 [h / mm], B = 450 [h], and the guaranteed time is 2000 [h], 100d + 450 = 2000 → d1 = 15.5 [mm].

Further, when a similar test was performed using a sealing resin of k2 (moisture permeability): 3.8 g · [m / mm ² 24 h], when 5 mm: A + B = 1700 [h], 10 [mm] : A + B = 2900 [h], so when 5 [mm]: 5a + B = 1700 [h], 10 [mm]: 10a + B = 2950 [h], a = 250 [h / mm], B = 450 [h] and guarantee time was 2000 [h], 250d + 450 = 2000 → d2 = 6.2 [mm] was obtained.

  From this, it is proved that the time for the electrode to deteriorate due to B: reached moisture is constant in the constant element regardless of the sealing resin 18.

On the other hand, A: The time for moisture to pass through the sealing resin and reach the capacitor element is k1 (moisture permeability): 9.5 [g · mm / mm ² · In the case of a sealing resin of 24 h], the thickness d1 = 15.5 [mm] and k2 (moisture permeability): 3.8 [g · mm / mm ² · 24 h], the thickness d2 = 6.2 [ mm] is necessary, d1 / k1 = 15.5 / 9.5 = 1.63, d2 / k2 = 6.2 / 3.8 = 1.63, and the thickness and moisture permeability of the sealing resin There is a fixed relationship between the two, i.e. d = 1.63k.

  That is, in the 85 [° C.]-85 [%] RH moisture resistance load test required for metallized film capacitors for in-vehicle use, etc., the guaranteed time of 2000 [h] for the capacitance change rate to be within 5 [%]. For this, the relationship between the thickness of the sealing resin 18 and the water vapor transmission rate may be: d = 1.63 · k or more.

Here, in order to set the guarantee time to h, since the moisture intrusion time is proportional to the thickness of the sealing resin, d = 1.63 · k · (h / 2000). In order to set the steam partial pressure to P, it is necessary to increase the thickness of the sealing resin in proportion to the steam partial pressure,
d = 1.63 · k · (h / 2000) · (P / P0) (3)
Where P: water vapor pressure under moisture resistance test conditions
P0: Water vapor pressure at 85 ° C. and 85% RH.

Here, when a moisture resistance test is performed, using a general formula,
A = k (p1-p2) .S / d (4)
Therefore, the amount of water vapor passes through from the beginning of the test by the amount of A in the formula (4).

  However, in order to be in a state of deteriorating the electrodes of an actual film capacitor, as described above, the total time of A time and B time is A time is resin transmission time + element interface transmission time (particularly metallicon part), The time required for permeation while causing a hydration reaction in the metallicon part is complicated, and it was unclear how much water vapor can permeate in the above general formula from the time when the film capacitor starts to deteriorate.

  Therefore, in the metallized film capacitor of the present invention, the moisture permeability of the sealing resin 18 for producing a resin-filled film capacitor satisfying a certain test condition / guarantee time by performing a separation analysis of A time and B time. The relationship between thickness and thickness is clarified, and high moisture resistance is achieved.

[Second Embodiment]

  The second embodiment is an example of a structure of a metallized film capacitor device using the metallized film capacitor described above and a manufacturing method thereof.

  The second embodiment will be described with reference to FIG. 6 and FIG. FIG. 6 shows an example of a metallized film capacitor device, and FIG. 7 shows a bus bar connection. 6 and 7, the same parts as those in FIG. 1 are denoted by the same reference numerals.

  As shown in FIG. 6, the metallized film capacitor device 4 includes an assembly 62 of metalized film capacitors 2, first and second bus bars 64 and 66, a plurality of insulating covers 68, a terminal board 70, and the like. Is provided.

  The assembly 62 aggregates a plurality of metallized film capacitors 2, and in this embodiment, the terminals 62 and 16 of the 15 metallized film capacitors 2 are arranged in a common plane and arranged in 3 rows and 5 columns. ing. Although the tightening means is not shown, each metallized film capacitor 2 may be detachably disposed or may be fixed with resin.

  The bus bar 64 is means for connecting one terminal portion 14 of each metallized film capacitor 2 of the assembly 62, and is made of, for example, a copper plate. In this embodiment, it is comprised by the grid | lattice-like frame so that the terminal part 14 of each metallized film capacitor 2 may be straddled. As shown in FIG. 7, a through hole 71 is formed in the cross part of the bus bar 64. The screw part 44 of the terminal part 14 is passed through the through hole 71, and the nut 72 is fixed to the screw part 44 to fix the terminal part 14. The bus bar 64 is sandwiched between the nut 72 and the nut 72 and is electrically connected. Each terminal portion 14 is connected in parallel by a bus bar 64.

  The bus bar 66 is a means for connecting the other terminal portion 16 of each metallized film capacitor 2 of the assembly 62 and is configured in the same manner as the bus bar 64 to connect the terminal portions 16 in parallel.

  The insulating cover 68 is a protective means for protecting the connection portion between the terminal portions 14 and 16 of each metallized film capacitor 2 and the bus bar 64 or 66, and is a casing formed of an insulating material such as a synthetic resin. is there. By installing this insulating cover 68, the connection portion is protected and electrical insulation is achieved, thereby enhancing safety.

  External terminal portions 74 and 76 are installed on the terminal board 70, a bus bar 64 is connected to the external terminal portion 74, and a bus bar 66 is connected to the external terminal portion 76. Accordingly, as shown in FIG. 8, a plurality of metallized film capacitors 2 are connected in parallel between the external terminal portions 74 and 76 with the bus bars 64 and 66 interposed therebetween.

  In this embodiment, all of the plurality of metallized film capacitors 2 are connected in parallel. However, as another connection form, series connection or grouping of a plurality of capacitors may be used for series-parallel connection.

  Next, an example of a method for manufacturing a metallized film capacitor device will be described.

  This method of manufacturing a metallized film capacitor device includes a process of connecting the assembly 62 and the bus bars 64 and 66, a process of attaching the terminal board 70, and the like using the metallized film capacitor 2 described above.

  Each metallized film capacitor 2 is manufactured as described in the method for manufacturing the metalized film capacitor 2 described above. For example, fifteen metallized film capacitors 2 are prepared as the plurality of metallized film capacitors 2, and these are arranged in three rows and five examples, and the terminal portions 14 and 16 are arranged on one surface.

  A bus bar 64 is disposed in each terminal portion 14, a nut 72 is attached to the screw portion 44 of the terminal bolt 40 that is passed through the through hole 71 of the bus bar 64, and each terminal portion 14 of the metallized film capacitor 2 is attached to the bus bar 64. Secure and connect electrically.

  Similarly, a bus bar 66 is disposed in each terminal portion 16, a nut 72 is attached to the screw portion 44 of the terminal bolt 40 that is passed through the through hole 71 of the bus bar 66, and each terminal portion of the metallized film capacitor 2 is attached to the bus bar 66. 16 is fixed and electrically connected.

  Through such a connection process, an assembly 62 composed of a plurality of metallized film capacitors 2 is arranged between the bus bar 64 and the bus bar 66, and the metallized film capacitors 2 are connected in parallel by the bus bars 64 and 66. It will be in the state.

  A terminal board 70 is attached to each of the bus bars 64, 66 and the assembly 62, the bus bar 64 is connected to the external terminal part 74 in the terminal board 70, and the bus bar 66 is connected to the external terminal part 76. As a result, the metallized film capacitor device 4 is completed.

According to the metallized film capacitor device 4 and the manufacturing method thereof described above, the effects as described in the metallized film capacitor 2 and the manufacturing method thereof can be enjoyed, and the following effects can be obtained.

  (1) According to the metallized film capacitor device 4, since the metallized film capacitor described above is used for the assembly 62, it is possible to provide a capacitor device with improved moisture resistance, miniaturization, and robustness.

  (2) Since the terminal portions 14 and 16 are formed on the respective end faces of the metallized film capacitor 2 and the bus bars 64 and 66 are arranged and connected to the respective end faces of the different metallized film capacitors 2, the bus bars 64 and 66 are connected. , 66 can be made large, and a capacitor device with improved safety can be provided.

  (3) Since each metallized film capacitor 2 has sufficient moisture resistance, there is no need for a sealing measure such as a filling resin again for the entire assembly 62, and the terminal portions 14, 16 of each metallized film capacitor 2 are connected to each other. By simply connecting with the bus bars 64, 66, etc., the metallized film capacitor device 4 having good moisture resistance can be easily realized. In addition, the connection of the terminal portions 14 and 16 of the metallized film capacitor 2 by the bus bars 64 and 66 also eliminates mechanical stress on the metallized film capacitor 2 and the connection part to the capacitor element 6 inside thereof, and is robust. A metallized film capacitor device 4 can be formed.

  Moreover, since each of the metallized film capacitors 2 is open to the outside air, the heat dissipation is good.

  (4) Since each bus bar 64, 66 is arranged on the opposite side of the assembly 62 of the metallized film capacitor 2, safety is high and there is no risk of short-circuiting due to routing during bus bar wiring.

  (5) Since the outer container 8 and the lid portions 10 and 12 are fixed by the sealing resin 18 and the terminal portions 14 and 16 for external connection are fixed to the lid portions 10 and 12, the bus bar 64 66, the mechanical stress when connecting each metallized film capacitor 2 to the metallized film capacitor 2 and the capacitor element 6 in the metallized film capacitor 2 is stable, and the element state / connection state is stabilized. And no abnormal heat is generated even when a high current flows. In particular, the fixing between the outer container 8 and the lid portions 10 and 12 is very stable by sealing with the sealing resin 18, and the element state and the connection state can be stabilized.

[Third Embodiment]

  The third embodiment is an example of a structure of a metallized film capacitor device using the metallized film capacitor described above and a manufacturing method thereof.

  The third embodiment will be described with reference to FIG. FIG. 9 shows a configuration example in which the capacitor element is positioned by the lid. 9, the same parts as those in FIG. 1 are denoted by the same reference numerals.

  In this embodiment, a single or a plurality of stoppers 78 may be formed in the closing portions 34 of the lid portions 10 and 12, and the fixed position of the capacitor element 6 may be positioned by the height h of the stoppers 78. The stopper 78 may be ring-shaped, arc-shaped or rod-shaped. If it is rod-shaped, the capacitor element 6 can be positioned in a horizontal state by a plurality of stoppers 78, and the position can be stabilized.

Although not shown in the drawings, a protrusion for positioning the opening end of the outer container 8 is provided in the closing part 34 of the lid parts 10 and 12, and the protrusion is provided between the inner side of the lid part 10 or 12 and the opening end of the outer container 8. A configuration may be adopted in which the above-described interval D ₅ is set.

  According to such a configuration, the capacitor element 6 and the outer casing 8 can be easily positioned by the stopper 78 in the lid portions 10 and 12. It is easy to manage the thickness of the resin layer of the sealing resin 18 and the application state of the metallicon to the electrode portions 20 and 22, and the moisture resistance characteristics that are effective, homogeneous and sufficient for the metallicon electrode portions 20 and 22 where water vapor penetrates most. Can be realized by the resin layer of the sealing resin 18. Furthermore, the product weight and size can be minimized by adjusting the resin thickness in accordance with the moisture resistance guarantee conditions.

[Other Embodiments]

In the said embodiment, although the cylindrical exterior container 8 and the cover parts 10 and 12 are used, it is not limited to this. A rectangular tubular outer container 8 and lid portions 10 and 12 may be used.

  Next, referring to the embodiment of the metallized film capacitor 2 or the metallized film capacitor device 4, the outer container 8 and the lid portions 10 and 12 may be formed using an insulating resin material or the like. When the outer container 8 is formed of a metal case, an insulating process may be performed on the inner surface side in which the capacitor element 6 is accommodated.

  A material with low moisture permeability is preferable for the outer container 8 and the lid portions 10 and 12, and by using such a material, a thinner outer container 8 can be formed, and weight reduction and improvement of heat dissipation can be achieved. . For example, polybutylene terephthalate resin, polycarbonate resin, polyphenylene sulfide resin, polyethylene terephthalate resin and the like are preferable.

  If the positioning projections of the capacitor element 6 are provided on the inner surfaces of the outer container 8 and the lid portions 10 and 12, the positioning of the capacitor element 6 with respect to the outer container 8 and the positioning of the outer container 8 and the lid portions 10 and 12 are facilitated. Become.

  Moreover, the sealing resin 18 is poured into the positioned lid portions 10 and 12 and is cured, so that necessary and sufficient resin sealing that is optimal for securing moisture resistance and reducing weight is possible. At this time, the exterior container 8 is attached to one of the lid portions 10, the sealing resin 18 is poured into the lid portion 10 side down, and the resin is sealed by thermosetting. Then, after the sealing resin 18 is solidified, the sealing resin 18 may be poured with the other lid portion 12 down. In this manner, the lids 10 and 12 are selectively filled with the sealing resin 18 by the attachment of the lids 10 and 12 and the position operation thereof, and the resin layer of the sealing resin 18 is formed by thermosetting. An epoxy resin, a urethane resin, or the like may be used for the resin material of the sealing resin 18. According to such a resin, moisture resistance can be improved.

  As described in the above embodiment (FIG. 1 and the like), the lid portions 10 and 12 attached to both ends of the outer container 8 are cap-like, so that the space between the lid portions 10 and 12 and the outer container 8 is formed in the space portion. By filling the sealing resin 18, it is possible to obtain a metallized film capacitor 2 having a very narrow and long water vapor intrusion path and good moisture resistance, and the outer container 8 and the lid parts 10 and 12. Fixing with the sealing resin 18 can be realized.

As described above, the most preferable embodiment and the like of the present invention have been described. However, the present invention is not limited to the above description, and is described in the claims or a form for carrying out the invention. It goes without saying that various modifications and changes can be made by those skilled in the art based on the gist of the invention disclosed in the above, and such modifications and changes are included in the scope of the present invention.

2 Metallized Film Capacitor 4 Metallized Film Capacitor Device 6 Capacitor Element 8 Outer Container 10, 12 Lid Part 14, 16 Terminal Part 18 Sealing Resin 20, 22 Electrode Part 24, 26 Electrode Layer 28 Opening 30, 32 Lead Part 31 Connection portion 56, 58 Dielectric film 62 Assembly 64 First bus bar 66 Second bus bar

Claims (6)

A winding element in which at least two dielectric films each having an electrode layer are wound, wherein a metal is sprayed on an end face of the element to be connected to one of the electrode layers, and the metal is sprayed on the end face of the element. A capacitor element comprising an electrode portion connected to the other of the electrode layers,
An opening member on each element end face side of the capacitor element, and an exterior member for storing the capacitor element;
A sealing member that is fixed to the exterior member with an interval between the element end face of the capacitor element and seals each of the openings;
A terminal portion fixed by penetrating the sealing member;
A lead portion fixed to and electrically connected to the terminal portion, and connecting the terminal portion and the electrode portion;
A sealing resin that is filled in the gap between the sealing member and the exterior member, covers the electrode part, and is in close contact with the sealing member to seal the exterior member and the sealing member;
A metallized film capacitor comprising:
The sealing member includes a closed portion that covers an opening end surface of the exterior member, and a standing wall portion that is formed at a peripheral portion of the closed portion and covers a peripheral surface of the exterior member,
The metallized film capacitor according to claim 1, wherein the sealing resin is filled between the standing wall portion and the exterior member.
The metallized film capacitor according to claim 1 or 2, wherein a thickness d of at least one of the sealing resin or the exterior member is equal to or greater than a value of the following formula.
d = 1.63 · k · (h / 2000) · (P / P0)
d: Thickness (mm)
k: moisture permeability (g · mm / mm ² · 24h)
h: Moisture resistance reliability guarantee time (hours)
P: Water vapor pressure (Pa) under moisture resistance guarantee test conditions
P0: Water vapor pressure at 85 ° C. and 85% RH (Pa)
A capacitor assembly in which a plurality of metallized film capacitors according to claim 1, claim 2 or claim 3 are juxtaposed,
A bus bar connecting between one or the other terminal portion of the metallized film capacitor of the capacitor aggregate;
And a plurality of the metallized film capacitors connected in series, parallel or series-parallel by the bus bar.
A winding element in which at least two dielectric films each having an electrode layer are wound, wherein a metal is sprayed on an end face of the element to be connected to one of the electrode layers, and the metal is sprayed on the end face of the element. Forming a capacitor element comprising an electrode portion connected to the other of the electrode layers,
Providing an opening on each element end face side of the capacitor element, and forming an exterior member for housing the capacitor element;
A sealing member that includes a lead part that connects the terminal part and the electrode part together with the terminal part, and is fixed to the exterior member with a space between the element end surface of the capacitor element and seals each of the openings. Forming a step;
Filling the gap between the sealing member and the exterior member with a sealing resin that covers the electrode portion and closely contacts the sealing member to seal the exterior member and the sealing member;
A method for producing a metallized film capacitor, comprising:
Forming a capacitor assembly by juxtaposing a plurality of metallized film capacitors obtained by the method for producing a metallized film capacitor according to claim 5;
Connecting one or the other terminal portion of the metallized film capacitor of the capacitor assembly by a bus bar, connecting a plurality of the metallized film capacitors in series, in parallel or in series; and
A method of manufacturing a metallized film capacitor device, comprising:

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